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Triakis semifasciata
Triakis semifasciata (''Leopard shark)' Kingdom: '''Animalia Phylum: Chordata Class: Chondrichthyes Order: Carcharhiniformes Family: Triakidae Genus: Triakis Species: Triakis semifasciata Environment: milieu, climate zone, depth range, distribution range: Marine; brackish; demersal; depth range 0 - 156 m, usually ? - 6 m. Subtropical; 45°N - 19°N, 126°W - 105°W. Distribution: Eastern Pacific: Oregon, USA to the Gulf of California. Size, weight, age: Max. length: 1.98 m (male), 1.80 m (female), common length: 1.60 m; weight: 18.4 kg; age: 30 years Short description: The leopard shark has a moderately stout body, with a short, rounded snout. There are well-developed, triangular flaps of skin in front of the nares. The eyes are large and oval, with a nictitating membrane (a protective third eyelid). The line of the mouth is strongly curved. There are furrows at the corners of the mouth extending onto both jaws, with those on the lower jaw almost long enough to meet at the midline.3 The tooth rows number 41–55 in the upper jaw and 34–45 in the lower jaw; each tooth has a slightly oblique, smooth-edged cusp in the center and 1–2 small cusplets on either side. These teeth are arranged into a flat, "pavement"-like surface with overlapping ridges. The large first dorsal fin is positioned about halfway between the pectoral and pelvic fins; the second is almost as large as the first and much larger than the anal fin. The pectoral fins are wide and triangular. The lower lobe of the caudal fin is well-developed in adults but less than half the length of the upper lobe, which has a strong ventral notch near the tip. The coloration is unique, consisting of prominent black "saddles" and large black spots running along the back, on a silvery to bronzy gray background. Adult sharks often have more spots and saddles with lighter centers compared to juveniles. The underside is whitish and plain. The average length of a leopard shark is 1.2–1.5 m (3.9–4.9 ft). Rarely males may grow to 1.5 m (4.9 ft) and females 1.8 m (5.9 ft), and there is a record of an exceptional female that measured 2.1 m (6.9 ft) long. The heaviest known leopard shark weighed 18.4 kg (41 lb). Biology: Found in shallow water from the intertidal to deeper waters, most commonly in enclosed muddy bays; including estuaries and lagoons (S. Wilson, pers. comm.). Prefer sandy areas, mud flats, and bottoms strewn with rocks near rocky reefs and kelp beds. Feed mainly on crabs, shrimps, bony fish, fish eggs, clam necks and innkeeper worms among a large variety of food in its diet. Form mixed schools. Ovoviviparous (aplacental), with 4 to 29 young in a litter. Utilized fresh or frozen for human consumption. Life cycle and mating behavior: Females produce 6-24 young, which are 20-23 cm long at birth. Ovoviviparous, embryos feed solely on yolk. Main reference: Compagno, L.J.V., 1984. FAO Species Catalogue. Vol. 4. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part 2 - Carcharhiniformes. FAO Fish. Synop. 125(4/2):251-655. Rome: FAO. IUCN Red List Status: LEAST CONCERN (''LC)' '''CITES: Not Evaluated CMS: Not Evaluated Threat to humans: Harmless Human uses: Fisheries: commercial; gamefish: yes; aquarium: commercial. Category:Triakidae, Houndsharks